it's like an emerging religion. some churches now offer gluten-free communion wafers. this is no longer a fad. it's a business. >> why are you eating gluten-free? >> because she's eating it. >> okay. >> what is gluten? >> some kind of wheat. >> gluten is a protein found in wheat, rye, and barley, so it's in baked goods and cereals, but because it acts as a sticky binding agent, it's also in soups, gravies, sauces, salad dressings, even hot dogs and ketchup. but some people just can't digest gluten. if they eat it, they'll get sick. about 1% of americans have ciliak disease, coming with rashes or joint pain. what's interesting is that there aren't nearly enough people who have medical problems with gluten to explain the giant surge in gluten-free products. >> we know have over 300 gluten-free products. >> don is a marketing manager for general mills. >> ranging from yogurt, progressive soups, all the way to our chex flavors as well as betty crocker. >> is there any scientific proof that if you're not part of that extremely small minority of americans who are sensitive t